1. Field of the Invention
The present invention relates to a component of a display panel and a method for fabricating thereof. More particularly, the present invention relates to a color filter and a method for fabricating thereof.
2. Description of Related Art
With the advantages of high resolution, small volume, light weight, low drive voltage, low power consumption, and a wide range of applications, the liquid crystal display (LCD) has replaced the cathode ray tube (CRT) as the mainstream of the new generation display. In general, the method for fabricating a color filter substrate of an LCD includes three photolithography processes by using color photo resists with primary colors, wherein three color filter films are formed in sequence in corresponding pixel regions on a substrate and form the color filter substrate. More specifically, the color filter films are formed by coating color photo resists on the substrate. The method of coating color photo resists is usually performing spin coating to uniformly coat on the substrate. Therefore, a great part of the color photo resist is wasted in the spin coating process and the fabricating cost is increased. In addition, in order to uniformly distribute the color photo resists during the coating process, a large amount of organic solvent is generally used in the color photo resist. Other processes such as a soft bake or a hard bake process are performed after the coating process to cure the color photo resist to form the color filter film.
A conventional technology which uses an inkjet printing (IJP) process to form a color filter substrate has been developed. The IJP process may print color inks of three primary colors to formed color filter films in pixel regions. Compared with the conventional photolithography process of fabricating color filter films, the IJP process may reduce costs of manufacturing and materials. For forming the color filter films, the IJP technology has advantages of saving fabricating cost and large area manufacturing.
The conventional color filter substrate includes a black matrix layer and color filter films of the three primary colors, red, green, and blue. As shown in FIG. 1A, a black matrix player 120 is formed by coating resin photo resist on the substrate and subsequent processes such as soft bake, exposure, development, and hard bake are performed in sequence to form the black matrix layer 120. Next, color ink is inkjet printed in a pixel region P. In addition, a treatment process is generally performed after the black matrix layer is formed to prevent the color inks from overflowing onto the black matrix layer 120, causing color intermixing in the pixel. The surface of the black matrix layer 120 has a hydrophobic characteristic after the treatment process such that the color inks would hardly adhere onto the black matrix layer 120 and flow into the pixel region P.
However, no matter the black matrix layer 120 made of resin photo resist is fabricated by liquid photo resist coating or dry film attaching, the resin photo resist is usually subjected to the abovementioned treatment process by an atmospheric pressure plasma process after exposure, development and hard bake, for example. Some scum 122 may easily remain at the intersection region between the black matrix layer 120 and the substrate 110 after the black matrix layer 120 has been bombarded by plasma. In addition, the scum 122 itself also has a hydrophobic characteristic, resulting in a situation that after color inks are filled in the black matrix layer 120, the edges of the black matrix layer 120 are not filled and thus a color filter layer 130 as shown in FIG. 1B is formed. As such, problems such as light leakage and non-uniform colors may occur and reduce the display quality of the LCD panel. Furthermore, as shown in FIG. 1B, after color inks are filled in the pixel region, influencing factors such as material of the color inks, surrounding environment, and surface tension of the black matrix layer 120 cause the surface of the color filter film to form a convex surface of non-uniform thickness on the substrate and further influence color performance.